Climate change catastrophe took just months

Six months is all it took to flip Europe’s climate from warm and sunny into the last ice age, researchers have found.

They have discovered that the northern hemisphere was plunged into a big freeze 12,800 years ago by a sudden slowdown of the Gulf Stream that allowed ice to spread hundreds of miles southwards from the Arctic.

Previous research had suggested the change might have taken place over a longer period — perhaps about 10 years.

“It would have been very sudden for those alive at the time,” said William Patterson, a geological sciences professor at the University of Saskatchewan in Saskatoon, Canada, who carried out the research. “It would be the equivalent of taking Britain and moving it to the Arctic over the space of a few months.”

His findings, published at a recent conference, reinforce a series of studies suggesting that the earth’s climate is highly unstable and can flip between warm and cold very rapidly with the right trigger.

Originally posted by bobs_uruncle
It's all just opinions...

The new description, reminiscent of the Hollywood blockbuster The Day After Tomorrow, emerged from one of the most painstaking studies of past climate changes yet attempted.

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Most such research is based on analysing cores drilled from ice or from the sediment found at the bottom of oceans or lakes. In such cores the ice or sediment is found in layers whose composition shows what the climate was like at the time they were laid down.

Ice cores drilled from the Greenland ice cap have already shown that the big freeze of 12,800 years ago — known as the Younger Dryas mini-ice age — happened fast but lacked the detail to pin it down precisely.

Patterson, however, obtained mud deposits from Lough Monreagh, a lake in western Ireland, a region he says has “the best mud in the world in scientific terms”.

Patterson used a precision robotic scalpel to scrape off layers of mud just 0.5mm thick.Each layer represented three months of sediment deposition, so variations between them could be used to measure changes in temperature over very short periods.

Patterson found that temperatures had plummeted, with the lake’s plants and animals rapidly dying over just a few months. The subsequent mini-ice age lasted for 1,300 years.